1. Field of the Invention
The present invention relates to systems for communication primarily for electronic controllers related to refrigeration containers, where a number of containers are connected to a power source, where at least one electronic controller comprises means for communication.
2. Description of Related Art
The present invention further relates to a method for communication to and from communication systems where a number of containers are connected to a power source, where the method for communication performs bidirectional communication with other communication systems or a gateway unit.
US 2004/0196182 A1 concerns Intelligent Mobile Asset Management System for intelligently tracking and monitoring physical assets worldwide using solar cells, rechargeable battery, two-way satellite communications, a CPU with memory, sensors of various types and GPS in the device and a GIS (Geographic Information System) database for storing and reporting the location and condition of the asset. The apparatus is permanently mounted on the physical asset, e.g., a cargo container, portable construction equipment, etc., where it reports its position and condition to the based unit, based on, movement, a container door being opened, overheating, etc., time passage or on-demand, using satellite communication networks. These reporting criteria are controlled by the system and are set and reset as needed.
In this document, communication is performed directly to and from the containers to communication satellites. This is possible in terms of train and lorry transport, but in container ships only a limited number of containers will be able to communicate with the satellite.
U.S. Patent Application Publication 2007/0040647 A1 concerns System for Monitoring and Control of Transport Containers, which system comprises a unit and system for remote monitoring and controlling of various conditions in a container. The system includes a local wireless or cable (wired) network with a local station and access points positioned in the vicinity of location of containers, a remote central station connected with the Internet and a container mounted means for monitoring and control of reefer equipment, each of which includes a processor (CPU) and a transceiver of wireless local communication, a GPS-receiver and a transceiver of cellular communication. In addition the processor (CPU) of the device is connected to the controller of reefer equipment, while the transceiver of wireless local communication is made so that the creation of Personal Area Network (PAN) with mobile electronic devices (e.g., Notebook, Pocket PC, PDA) is possible, and establishment of wireless communication with a communication gateway of the said local network is also possible.
The document U.S. Pat. No. 7,323,981 B2 Container Tracking System describes shipping containers which are networked for transferring data between the shipping containers. The shipping containers include sensors for detecting hazardous conditions associated with the shipping containers. The hazardous condition sensed by any shipping container on a ship is transmitted through the network to a satellite transmitter and/or a radio transmitter for reporting to a central database.
U.S. Patent Application Publication 2008/0090523 A1 concerns container tracking unit. A short range radio is communicating with labour container units or by a gateway unit. The short range radio can communicate through another container unit to the gateway unit. The container unit also comprises a cellular network radio that can communicate to a cellular network. In operation, at first the container unit tries to get access to the gateway unit over the short range radio, and if that does not succeed, the cellular network radio is used to receive connection information.
U.S. Patent Application Publication 2008/0056191 A1 and corresponding to U.S. Pat. No. 7,529,561 B2 also concerns short range radio communication from a container unit to a gateway unit or through another container unit. In the pending application, cellular network radio is also used for further communication and for receiving setup information for the short range radio. In the description on page 3, line 0050, the short range radio 103 complies with the first 802.11 standard specified by the IEEE or some variants of the first 802.11 standard, such as 802.11b, or some technique intended for short range radio communications. Furthermore, the cellular network radio operates in at least one of the following networks: TDMA (time division multiple access), a GSM (global system for mobile communications) network, a CDMA (code division multiple access) network; a FDMA (frequency division multiple access) network, or a UMTS (universal mobile telecommunications system) network. Furthermore, it is described that the cellular network radio may be a multi-frequency phone such as GSM 900/GSM 1800/GSM 1900 phone.
All of the above-mentioned patent applications are limited to the use of a cellular network radio. These cellular network radios need to communicate via a cellular network, for example to a monitoring server. The limitation of the cellular network radio and a cellular network indicates that mobile phone communication is necessary at least for setting up the short range radio communication. This mobile communication can only be performed as long as there is a cellular network available.
Modern refrigerated containers are complex machinery which typically includes an electronic controller to manage at least the temperature control. The temperature needs to be maintained with sufficient accuracy to protect the cargo, while keeping energy consumption at a minimum. The temperature control has to be performed under very variable circumstances, high and low ambient temperatures, high and low ambient humidity and cargo being loaded at different conditions. This calls for a high level of sophistication which typically causes occasional software updates to improve operation and adapt to new conditions.
Updating software in refrigerated container electronic controllers is, however, is, however, a logistically difficult task. The containers are typically in operation, spread around the world in a global operation, and the need to access the container physically to load and activate new software, which is a manual process, is time-consuming and a logistical problem. While the software update process itself might be only a matter of minutes, the process of accessing the entire container fleet over a limited period of time to ensure that software updates are implemented within reasonable timeframe, is a virtually impossible task. Software distribution in a container fleet can take years before the software update is performed in all the electronic container controllers.